Vacuum furnaces are known and used for brazing metal parts to form an integral body or component. The known vacuum brazing furnaces are most effective with parts having relatively small cross sections. The vacuum brazing of very large metallic bodies has been complicated by two factors: non-uniform heating of the parts being brazed and a limited ability to maintain the parts in intimate contact during the brazing process. Either factor results in ineffective brazing. Accordingly, there is a need for a vacuum furnace for use in the brazing of very large metallic bodies that overcomes those problems.
A vacuum furnace that is designed for brazing very large parts is a highly complex system which is very expensive to build and maintain. The high cost of such a furnace adversely affects the return on the investment in the system if its utility is limited to a single purpose. Accordingly, a need has arisen for a vacuum furnace that can be used not only for brazing of large metal parts, but also for other types of heat treating cycles. Therefore, it would be desirable to have a vacuum heat treating furnace which can accommodate different types of workpiece loads and which can be operated to perform different types of heat treatments on such loads.